A fourth class-action lawsuit has been leveled against the Capitol Police Department, and those involved aren’t backing down.

Approximately fifty officers, civilians and employees have filed a suit in U.S. District Court. They allege that they have been subjected to “continuous, pervasive and egregiously discriminatory actions” by the Capitol Police, as expressed in a statement released Wednesday by the U.S. Capitol Black Police Association.

Hostile work environments, reprisals, denial of promotions, age discrimination and denial of career-enhancing opportunities are just some of the allegations of discrimination outlined in the lawsuit.

“The Chief of Police, Phillip Morse, and members of the Capitol Police Board, have done little, if anything, to eliminate the obvious inequities that have negatively impacted the careers of African-American officers and employees,” the association claims.

In 2001, nearly 300 Black Capitol Hill police officers and employees filed a lawsuit citing discrimination by the Capitol Police Board. The current action lawsuit comes more than a decade after the unresolved dispute.

“The United States Capitol Police Department continues to project a model culture of discrimination as reflected in a 'modern day version of a 19th Century Southern Plantation in law enforcement," association member and Capitol Police Lt. Frank Adams said in a previous complaint.

The Black Police Association claims that the case highlights a lack of progress toward racial and gender equality within the U.S. Capitol Police since the case was initiated eleven years ago.